Tobacco sucker control

ABSTRACT

SUBSTITUTED 3-PYRIDYLMETHANES HAVING THE FORMULA   3-(R-C(-R&#39;&#39;)(-X)-)PYRIDINE   ARE APPLIED TO GROWING TOBACCO PLANTS TO INHIBIT THE GROWTH OF LATERALS, OR SUCKERS, ON SUCH PLANTS.

United States Patent Ofice 3,744,933 Patented July 10, 1973 Int. Cl. A0111 /00 US. Cl. 7178 11 Claims ABSTRACT OF THE DISCLOSURE Substituted 3-pyridylmethanes having the formula are applied to growing tobacco plants to inhibit the growth of laterals, or suckers, on such plants.

CROSS-REFERENCE This application is a division of our copending application Ser. No. 867,058, filed Oct. 16, 1969, which, in turn, is a continuation-in-part of our then eopending application Ser. No. 785,737, filed Dec. 20, 1968, now abandoned.

BACKGROUND OF THE INVENTION In the prior art, DAmico, US. 3,155,671 (-Nov. 3, i964) teaches the preparation of derivatives of 2-thiopyridine-l-oxide, which destroy or control undesired vegetation.

Johnson et al., Belgian 645,271 (Sept. 16, 1964), teach the use of 4-hydroxytrihalo (or tetrahalo) pyridines as herbicides. These pyridine compounds were applied to the foliage of cucumber plants and wild grass to kill the wild grass.

In addition, Kovikov et al., Khim v. Selsk. Khoz. 4 (6), 435-7 (1966), tested scmiand thiosemicarbazones of 2-, 3-, and 4pyridinecarboxaldehyde and teach the thiosemicarbazone of Z-pyridinecarboxaldehyde as having the highest herbicidal activity.

Van Heyningen US. Pat. No. 3,396,224 discloses the use of 3-substitnted pyridines similar to those of the present invention to control fungi on food crops and ornamental plants.

SUMMARY We have now discovered that the growth of laterals, or suckers, on growing tobacco plants is inhibited by the application to such plants of an effective amount of a compound of the formula DESCRIPTION OF THE PREFERRED EMBODIMENT The compounds employed in the novel process of this invention are substituted 3-pyridylmethanes having the following formula:

X l-R 1 X is hydrogen, hydroxyl, C -C alkoxy, amino, or cyano;

C -C alkoxy, C1C12 alkyl,

C -C alkenyl, CrCg alkynyl, C -C cycloalicyl, or C -C cycloalkenyl;

R is R, pyridyl, or thienyl;

each Q independently is halo, nitro, C -C alkyl, C -C alkoxy, trifiuoromethyl, C -C alkylthio, C -C alkyl-SO--, or C -C alkylSO or two Qs taken together are methylenedioxy; 'each n independently is an integer of 0 to 3; and

m is an integer of 1 to 3;

and the acid addition salts thereof.

In the process of this invention a composition containing one or more of the above-described pyridylmethanes is applied to growing tobacco plants to inhibit the growth of laterals,or suckers, on such plants.

While a numberof substituents have been indicated for the phenyl groups in the above formula, it will be apparent to those skilled in the art that other substituents may also be used, and that substitution may occur on other than the phenyl groups. When there is more than one substituent present they may be the same or diiferent. Compounds hearing such substituents are thus to be considered to be within the scope of this invention.

In the above formula, C -C alkoxy can be, for example, methoxy, ethoxy, isopropoxy, butoxy, pentoxy, and hexoxy.

The C -C alkyl groups can be, illustratively, methyl, ethyl, propyl, isopropyl, n-butyl, sec.-butyl, tert.-butyl, namyl, isoamyl, sec.-amyl, n-hexyl, isohexyl, sec.-hexyl, n-heptyl, isoheptyl, sec.-heptyl, n-octyl, sec.-octyl, isooctyl, nonyl, decyl, undecyl, dodecyl, and the like.

C -C cycloalkyl can be, illustratively, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexy, cycoheptyl, and cyclooctyl.

The alkenyl and alkynyl groups can be such as vinyl, allyl, l-butenyl, Z-pentenyl, 2-octenyl, l-butynyl, 2- propynyl, 2-hexynyl, and l-octynyl.

Suitable cycloalkenyl groups include cyclohexenyl, cyclopentenyl, cyclobutenyl, cyclooctenyl, and norbornenyl wherein Halo includes chlorine, bromine, iodine, and fluorine. The acid addition salts of the compounds represented by the generic formula supra are represented by those formed with hydrochloric, hydrobromic, hydriodic, sulfuric, nitric, p-toluenesulfonic, maleic, acetic, and malonic acids and the like.

Examples of compounds which have the desired activity and which can be successfully employed as tobacco desuckering agents in accord with the novel processes of this invention include, but are not limited to, the following:

3- [bis- 4-fiuorophenyl) methyl] pyridine cz- (4- chlorophenyl -a-cyclopropyl-3-pyridinemethanol a,wBis(2-chlorophenyl)-3-pyridinemethanol hydrochloride 41- 2,4-dichlorophenyl -a- (4-fluorophenyl) -3-pyridinemethanol hydrochloride (4-fluorophenyl) -a-phenyl-3-pyridinemethanol hydrochloride or, a-Bis (n-pentyl -3-pyridinemethanol hydrochloride a- (2-chlorophenyl) -cc- (4-fluorophenyl) -3-pyridinemethanol hydrochloride a- (n-hexyl) -a-methyl-3-pyridinemethanol 3- 1-isobutyl-3-methylbutyl pyridine oz,a-'BiS(iSObuty1)-3 -pyridinemethanol a- (2, -dimethylpheny1) air-phenyl-3-pyridinemethanol hydrochloride a-ChlOrO-a, u-bis- (4-chlorophenyl) -3-pyridylmethane hydro chloride oz,ot-BiS- 4-chlorophenyl) -3-pyridylmethylamine hydrochloride a, ot-BiS- (4-chlorophenyl) -3-pyridylmethyl methyl ether a-Cyclobutyl-a- (4-rfluorophenyl) -3-pyridinemethanol u-Pentafluorophenylu-phenyl-3-pyridinemethanol 3- u-methyl-4-chlorobenzyl) pyridine hydrochloride 3- (dicyclohexylmethyl pyridine a,ot-Bis (cyclohexyl) -3-pyridinemethanol a, oc-Bis (isopropyl) -3-pyridinemethanol 3 l- (n-heptyl -n-octyl] pyridine a, a-Bis isopentyl) -3 -pyridinemethanol hydrochloride 3- a-CYClOhfiXYl-otl-cyclohexenyl) methyl] pyridine oz, oc-BiS n-hexyl) -3 -pyridinemethanol hydrochloride :1, a-Diphenyl-3-pyridineacetonitrile cc- (3-ethyl-n-pentyl) -a-isobutyl-3-pyridinemethanol hydrochloride a, ot-Bis (cyclopropyl) -3-pyridinemethanol hydrochloride 0:, u-Bis n-propyl -3-pyridinemethanol hydrochloride 0:,oL-BiS (4-iodophenyl) -3-pyridylmethane p-toluenesulfonate m-Phenyl-a- (4-chlorobenzyl) -3-pyridylmethane a-Phenyl-a- 2-thienyl-3 -pyridylmethane u- 4-chlorophenyl) -a- (Z-thienyl) -3-pyridylmethane maleate a- 3 ,4-dichlorobenzyl) -oz- 3-ch1orophenyl -3-pyridylmethane a- (4-methylthiophenyl --phenyl-3-pyridylmethane 3- a-n-butylbenzyl) pyridine a- (4-ethoxyphenyl) -a-phenyl-3-pyridylmethane hydrobromide cam-Bis 4-ethylphenyl -3-pyridylmethane oxalate Owl-Bis 4-nitrophenyl -3-pyridylmethane m-(3-bromopheny1)-u-phenyl-3-pyridylmethane sulfate a,a-Bis( 3-bromophenyl) -3-pyridylmethane nitrate a-cyclopentyl-u- 4- chlorophenyl )-3-pyridylmethane a-cyclohexyl-a- (3-bromophenyl -3-pyridylmethane a- 2- chlorobenzyl) -a-cyclooctyl-3-pyridylmethane a-phenyla- (3-thienyl) -3-pyridylmethane oc-(4-chl01'0phenyD-ot- (2pyridyl)-3-pyridylmethane u-Cyano-a-phenyl-u- (3-thieny1) -3pyridylmethane Tri- 3-pyridyl methane u, oz-BiS- 4-iodophenyl) -3-pyridinemethanol a- (Z-fluorophenyl) qua-phenyl-3-pyridinemethanol a-(Z-butenYD-a-(4-methoxybenzyl)-3-pyridinemethanol a-(4-iodobenzyl)-u-(4-pyridyl)-3-pyridinemethanol a,a.-Bis-(2-phenylethyl)-3-pyridinemethanol a-n-Amyl-u-n-hexyl-3-pyridinemethano1 a,u-Bis(n-undecyl)-3-pyridinemethanol a-n-Hexyl-a-n-heptyl-3-pyridinemethanol age-Bis(cyclohexylmethyl)-3-pyridinemethanol hydrochloride a-Isopentyl-a-isohexyl-S-pyridinemethanol hydrochloride a-n-Undecyl-u-n-nonyl-3-pyridinemethanol sulfate a,a-Bis(isopentyl)-3-pyridinemethanol hydrobromide a-n-Dodecyl-u-n-octyl-3-pyridinemethanol phosphate a,a-Bis(n-hexyl)-3-pyridinemethanol sulfate a,a-Bis(n-undecyl)-3-pyridinemethanol phosphate a x-Bis(sec.-nonyl)-3-pyridinemethanol oxalate a,a-Bis(n-dodecyl)-3-pyridinemethanol hydrochloride a,a-Bis(undecyl)-3-pyridinemethanol hydrochloride a,a-Bis(n-octyl)-3-pyridinemethanol hydrobromide,

and the like.

The preferred compounds are those in which X in the above formula is hydrogen or hydroxyl.

The compounds are formulated for use either as dusts, spray concentrates, spreadable granules, or wettable powders. Those compounds which are soluble in water are readily formulated as emulsion-type sprays or wettable powders. Compounds which are less soluble in water are desirably formulated with a wetting agent or surfactant for the preparation of emulsion-type sprays or wettable powders. The wetting agent or surfactant used in formulating the emulsion-type sprays or wettable powders can be, illustratively, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan monolaurate, polyglycol ether sulfonate, alkylamine dodecylbenzenesulfonate, and the like. In the preparation of spreadable granules, the solid diluent used can be calcined attapulgite clay. Dry dispersions can be prepared on inert carriers such as vermiculite, peat moss and the like.

The compounds useful in this invention are conveniently prepared by methods well known to the art. Thus, the 3-pyridylmethane derivatives are readily synthesized by the methods taught by Van Heyningen et al., U.S. 3,397,273 (Aug. 13, 1968); and the 3-pyridinemethanols and derivatives thereof are made available by methods taught by Van Heyningen, US. 3,396,224 (Aug. 6, 1968). In particular, the a,a-dialkyl-substituted 3-pyridinemethanols are prepared according to the teaching of Wibaut et al., Rec. Trav. Chim., 77, 1057, (1958). Those compounds wherein X is C1-C3 alkoxy, amino or cyano are prepared by methods disclosed in Belgian Pat. 714,003 and South African Pat. 68/2,417 for the preparation of analogous pyrimidine compounds.

To control the growth of suckers on tobacco plants the compounds described herein are applied to growing tobacco plants at a rate of 0.125 to 2 pounds per acre. For such application the compounds are formulated into sprays or wettable powders as described above and applied to the foliage of the plants. We have seen no injury to the tobacco plants at the rates used. The inhibition of sucker growth will be illustrated by the following example.

Example Growing tobacco plants were topped, suckers over one inch in length were removed, and each plant was sprayed with 20 ml. of a formulation containing the concentration of the test compound indicated in parts per million. The suckers on the plants were measured, and the growth of suckers on treated plants were compared to growth on untreated controls. One, two, or three comparisons were made at intervals of one to two weeks. In some cases, after the third measurement the suckers were removed, weighed, and the weights of suckers from treated plants compared with the weights of suckers from control plants. The percent of inhibition was then calculated from the following formula.

Percent inhibition control measurement-treated measurement control measurement X The results are summarized in the table.

TABLE I Tobacco Sucker Control Percent inhibition Conc., Compound p.p.rn. 1 2 3 Weight 1,000 51.6 36 75. 3-(2,2'-dichlorophenylmethy1) 1,800 70 44 86. pyridine 2,500 so 50 as.

3,600 87.8 70 5,000 91.9 76 99. 3-[1-(2chlorophenyl)-n-heptyl]- 500 30.1 51.9 pyridine 1,000 35.5 45.6 2,000 78.6 77.0

500 27.2 24.7 3-la-(n-pentoxy)benzy1]pyridine-. 1,000 M5 13.2 14. 2,000 43.9 41.4 43. 2-(2chloro-a-cyclohexylbenzyl) 500 10.6 7.8

pyridine 1,000 14.1 8.7

2,000 10.1 8.3 1 3 8 1% a? 3 a 4- rid lhe ten0l-4 0 6. py y) p 2,000 18.3 4.0 87. apt-B18 nent l i pyridine- 500 0 methrino luu n 1,000 30.3 1.0 57. ,000 7.7 1.3 35. u-(4-chlorophenyl)-a-(2,4diehloro- 500 0 0 benzyl)-3-pyridinemethanol 1 000 42.5 53.8 58. sulfate 2, 000 O 9. 7 a-Cyclobutylmt-(4-fiuorophenyD- 500 50.1 52.7 81. 3-pyricline methanol 1,000 78.6 83.2 64. 2,000 70.9 76.8 79. 1 idi 55 3- 1,2-di hen leth yr 'ne-.-- p y y)p ,000 47.5 65.8 47. 2-(2,5-d.irnethylphenyD-m-phenyl- 2,000 55.4 77.9 87. 71.4 .4 27.

3-pyridins methanol hydrochloride 2-(3 pyrldyl)-1-(4-chlorophenyl) 500 55 2-propanol .000 19 2,000 a-(mPentyl)fl-phenyl-Ii-pyri- 2000 43.1 dinemethanolhydrochloride 4,000 89.2 a,a-BiS(cycl0heXy1)-3- ,000 91.1 pyridinemethanol 4,000 79.3 3-pyridylchlorophenyl4- :100 60.6 ehlorobenzylcarbinol 1,13%) 27.?) zit-(4-ch1orophenyh-u-cyclopropyl- 2,000 91.1 90.2 85.6 91.4 3-pyridinemethanol hydro- ,000 93.9 100 100 100 chloride i at O 3- d ldi hen lmethane ,00

pyfl y p y 2,000 75.1 78.6 3[a-(2,5-dimethy1phenyl)- 2,000 93.9 98.4 99.1 99.7 benzyll-pyridine 000 88.2 95.1 97.3 99.0 a(ZchlorophenyD-wcyclohexyl- 500 51.3 48.6 56.2

2-pyridinemet-han0l 1,000 74.7 56.1 61.4

000 0 0 0 3-[bis(kchlorophenynmethyfl- 500 0 pyridine hydrochloride ,000 91.4 2,000 20 Bis(4ehlor0phenyl)-3- 500 0 pyrldylmethane 1,000 13.4 80.

2,000 74 85. 3-bis(2,5-dichloropheny0- 500 51.4

methylpyridine 1,000 43.2 .5.

2,000 100 idi 1 3 g 3-die clohex lmeth 1 run... ,00 y y ypyr ,000 94.1

It will be noted that 3-(2, 2'-dichlorodiphenylmethyl) pyridine is an especially active compound. Its activity is somewhat ditferent from presently-used tobacco desuckering agents in that it appears not only to depress the formation of new suckers, but also removes small suckers as well.

In addition to the above-described herbicidal and tobacco desuckering activity, the pyridine compounds described herein have been found to exhibit general plant growth inhibiting activity, especially with regard to foliar growth. For example, the application of 3-(2,2'-dichlorodiphenyhpyridine to blue grass at a rate. of 0.4 to 10 lbs/acre retards the growth of the grass leaves, thereby requiring less frequent mowing. The application of tit-(4- chlorophenyl)-m-cyclopropyl 3 pyridinernethanol to mature soybeans at a rate of 0.4 to 10 lbs./ acre retards foliar growth, permitting the plant to devote all its energy to fruit growth.

In general, application of the compounds may be as a foliar spray or a soil drench using techniques well known to those skilled in the art. At times, treatment may be effected by a seed soak treatment. In this method of treatment the seeds to be treated are allowed to stand in a solution of the compound for a period of several hours. The solution is prepared by dissolving the compound in an inert solvent such as acetone and diluting to the desired concentration with water containing a surface active agent.

We claim:

1. A method for inhibiting sucker growth to tobacco plants which comprises applying to growing tobacco plants an effective amount of a compound of the formula:

x -a if wherein Cr-C alkoxy, 01-012 alkyl, C -C alkenyl, C C alkynyl, C -C cycloalkyl, or C -C cycloalkenyl; R is R, pyridyl, or thienyl;

each Q independently is halo, nitro, C -C alkyl, C -C alkoxy, trifluoromethyl, C -C alkylthio, C -C alkyl-SO-, or C -C alkyd-SO or two Qs taken together are methylenedioxy; each n independently is an integer of 0 to 3; and m is an integer of l to 3; and the acid addition salts thereof.

2. A method as in claim 1 wherein the compound is applied to the plants at a rate between about 0.125 and. 2 pounds per acre.

3. A method as in claim 1 wherein X is hydrogen.

4. A method as in claim 3 wherein the compound is '3-(2,2'-dichlorodiphenylmethyl)pyridine.

5. A method as in claim 3 wherein the compound is 3-[m-(2,5-dimethylphenyl)benZyHpyridine.

6. A method as in claim 3 wherein the compound is 3- bis(2,5-dichlorophenyl)methylpyridine.

7. A method as in claim 1 wherein X is hydroxyl.

8. A method as in claim 7 wherein the compound is a-cyclobutyl-w(4-fluorophenyl)-3-pyridinemethanol.

9. A method as in claim '7 wherein the compound is a-(2,5-dimethylphenyl)-a-phenyl-S-pyridinemethanol hydrochloride.

10. A method as in claim 7 wherein the compound is w x-bis(cyclohexyl)-3-pyridinemethanol.

11. A method as in claim 7 wherein the compound is a-(4-chlorophenyl)-a-cyclopropyl-3-pyridinemethanol hydrochloride.

References Cited OTHER REFERENCES Novikov et al.: Chem. Abst, vol. 61 (1964), 882%. Milch; Chem. AbsL, vol. 57 (1962), 1316f.

LEWIS GOTTS, Primary Examiner C. L. MILLS, Assistant Examiner 

